Sealing strip



Feb. 28, 1956 R. J- BUSH ET AL SEALING STRIP Filed Jan. 50, 1955 H ZZ.sM 1 2%; Z m m w a 5 1. 4 L. q 1 5% W2 x 7 United States Patent O FSEALING STRIP Russell J. Bush, Dayton, and Cletus L. Moorman, Trotwood,Ohio, assiguors to General Motors Corporation, Detroit, Mich., acorporation of Delaware Application January 30, 1953, Serial No. 334,108

Claims. (Cl. 20-69) v This invention relates to elastomeric sealingstrips and more particularly to a sealing strip for use between twoabutting structures.

An object of the present invention is to provide an elongate elastomericstrip having a base portion and a plurality of hollow bulb-like membersintegrally formed thereon, each of said members having a predeterminedconfiguration and spacing therebetween for forming a plurality ofconfined air spaces when the members are deformed in the direction ofthe base.

A more specific object of the present invention is to provide a sealingstrip including a plurality of longitudinally extending bulb portionsparticularly adapted to compensate for variations between a door andframe closure. This object is materialized by providing an elongateelastomeric strip, secured to either the door or the closure, whichstrip is inherently adapted to form a plurality of confined air spaceswhen the strip is compressed as the door is brought into abuttingrelation with its closure. The plurality of confined air spaces areformed in situ during the closing process by utilizing a spacing betweenthe bulbs and configuration of hollow bulbs. The air spaces formedinclude confined air spaces between adjacent bulbs and a plurality ofspaces within the hollow bulbs formed as the hollow Within the bulb isdivided by the buckling of the bulb walls.

A further object of the present invention is to provide an elongateelastomeric composite sealing strip having a base portion and aplurality of vertically extending hollow dumbbell shaped bulb portionsintegrally formed and longitudinally extending thereon. Said bulbportions having a spacing therebetween and longitudinally extendingweakened wall portions constructed and arranged so that 2n|(nl) confinedair spaces are formed as the bulbs are sufficiently compressed in thedirection of the base, wherein n in the formula denotes the number ofindividual bulbs located on the base.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred embodiment of the present invention isclearly shown.

In the drawings:

Fig. 1 shows a fragmentary view in perspective of a section of animproved sealing strip showing a plurality of hollow bulbs on a base.

Fig. 2 is a sectional view of the strip in Fig. 1 showing the bulbscompressed between two structures.

Fig. 3 is a perspective view of the sealing strip in Fig. 1 mounted on aclosure.

In the drawings reference numeral 20 designates a composite sealingstrip having a base portion 22 adapted to be secured to a supportingstructure with or without the aid of reinforcing means 24 which aresupplied along extending edges 25 of the base portion 22. In Fig. 3 ofthe drawings numeral 26 indicates a closure and 28 a door adapted to fitinto said closure. The door 28 has an abut- 2,736,076 Patented Feb. 28,1956.

2 ting portion 30 and a raised portion 32. The abutting portion 30 ofdoor 28 is adapted to be brought into juxtaposition with the closure 26and raised portion 32 thereof is sized so as to be accommodated withinopening 34 for providing additional insulation tothe door 28. Thesealing strip .20 has base portion 22 secured about the peripheral edgesof the opening 34 and is positioned to engage abutting portion 30 ofdoor 28. e

In the form of the invention shown, the two longitudinally extendinghollow bulbs 40 are formed integrally with the base portion 22 each ofwhich include a wall portion 42 and a top portion 44 thereon. The bulbsare formed with longitudinal creases, folds or convolutions thereinwhich condition the wall toward bending or buckling in a predetermineddirection. This same condition may be accomplished by physicallyweakening the wall. In either case the term weakened portion isindicative of the action desired and will be used-in this generic sensehereinafter. Weakened portions 46 are provided in wall portions 42 for apurpose hereafter to be described. The bulbs 40, are spaced from eachother across base portion 22 thereby normally forming unconfined airspace 52 therebetween. A further single confined air space 54 isnormally present within the hollow portion of each bulb 40. I

In Fig. 2 the sealing strip (Fig. l) is shown as being compressedbetween a mounting structure 56 and a compressing structure 558. Whenthese two structures apply sufficient compressive force to the bulbportions 40 in the direction of the base 22 a plurality of confined airspaces will be formed. Said plurality of spaces consisting of confinedspace 60 formed from unconfined space 52 as the upper portions 44 ofadjacent bulbs are brought into juxtaposition and as the singular airspaces 54 are each divided in situ into two confined spaces 64 and 66when walls 42 are sufficiently buckled along weakened portions 46 sothat the central portions thereof touch.

Wiping ridges 50 may be included on bulbs 40 to further maintain a moreperfect seal between the bulb portion 40 and the compressing structure58. The spaces formed between ridges 50 are not considered as beingconfined air spaces as they are not a direct result of the deformationof the hollow bulb members.

The direction of pressure application should be at substantially rightangles to the plane of the opening being sealed, as shown by the arrowmarked A in Fig. 2. Swinging closures and the like may partially impairthe eificiency of the strip although its usefulness will be apparent insealing many applications of closures.

It is apparent that more than two bulbs may be included tocorrespondingly increase the number of confined air spaces formed andthus increase the sealing action of the strip when compressed. Thenumber of confined air spaces formed when the bulbs are sufficientlycompressed may be expressed by the formula 2n+(nl), where n equals thenumber of bulbs 40 spaced on the base 22.

It is also apparent that the sealing action of this strip is not whollydependent upon complete compression of the bulbs thus making the stripextremely useful in applications where considerable variation in thespacing between the door and its abutting structure is present, i. e.railroad refrigerator car doors. It is apparent that if the bulbs arenot fully compressed, the sealing action of the strip while impaired isnot completely eliminated as the insulating action thereof is maintainedthrough the confined air spaces normally present within the hollow bulbsand the confined air spaces between the bulb tops and the structure. Itis to be further noted that the strip can be attached to either a dooror closure by some suitable well known method such as nailing, screwing,gluing, etc.,

as the-method-of attachment and the structure -to which it is joined areincidental to the improved sealing action of the strip achieved by theplurality of air spaces formed by thecompressionxof the hollow bulbmembers.

While the embodimentof the present invention as herein disclosed,constitutes a preferred form, itis to be understood that other formsmight be adopted.

What is claimed is as follows:

1. An elongate composite elastomeric sealing strip adapted for sealingbetween two members comprising; a sealing strip having at least twospaced longitudinal extending sealing members each integrally associatedwith a base section and of substantially the same height andcross-sectional shape, each of said members being hollow and havingopposed side walls adapted to buckle inwardly and contact each otherwhen pressure is applied in the direction of the base whereby saidmembers form two hollow sections separated by the buckled portionthereof.

2. The sealing strip as set forth in claim 1 wherein longitudinalweakened portions are included along the sidewalls of the members, saidweakened portions providing means along which the side walls may bebuckled.

3. 'An elastomeric composite sealing strip between two structures; abase associated with one structure, and at least two hollow elastomericbulbs having a confined air space therein, said bulbs integrally formedwith the base and each having converging side portions, and topportions, and spaced from each other for providing an unconfined airspace therebetween, said bulbs being adapted to be deformed-when-the-structures-are brought in to an abutting relation with eachother, said deformed bulbs forming an unconfined air space betweencontacting top portions and at least two separated air spaces withineach hollow bulb when converging portions of the side walls contact eachother as suflicientpressure is applied in the direction of the base.

4. An elastomeric longitudinally extending composite sealing stripcomprising; a base portion adapted to'be associated with a supportstructure,and at least two hollow bulb portions integrallyassociated andtransversely spaced from each other on the base, said bulbshaving arelatively uniform wall thickness and having a dumbbell shape, saidbulbs forming a pluralitycof confined sealing chambers with the numberof chambers formed expressed as Zn-i-(n-l) where n equals the number ofbulbs transversely spaced on the base when the bulbs are deformed withsufiicient pressure applied in the direction of the base.

5. The sealing strip set forth in claim 4 wherein a plurality of wiperridges are integrally formed on a portion of the outer surface of thebulb.

References Cited in the file of this patent UNITED STATES PATENTS

